The present invention relates to a photomagnetic recording/reproduction apparatus (so-called mini-disk (MD) recorder) for performing photomagnetic recording on a disk-like recording medium (photomagnetic disk) and reproduction therefrom by converting an analog signal such as an audio signal, or the like, into a digital signal.
A photomagnetic recording/reproduction apparatus (MD recorder) for performing recording on a photomagnetic disk by converting an analog audio signal into a digital signal has been recently rapidly popularized as an audio signal recording/reproduction apparatus in place of an analog cassette recorder. Various techniques have been proposed to attain improvement of handling property of the photomagnetic recording/reproduction apparatus. For example, Japanese Patent Publication No. 9-213031A has disclosed a photomagnetic recording/reproduction apparatus in which searching for a target position can be performed at a high speed. For example, Japanese Patent Publication No. 9-44975A has disclosed a photomagnetic recording/reproduction apparatus in which an editing process such as track dividing, track erasing, etc. can be performed easily.
FIGS. 4 to 7 schematically show a series of operations in such a photomagnetic recording/reproduction apparatus in the case where a photomagnetic disk (hereinafter merely referred to as disk) is loaded into an apparatus body. Incidentally, FIGS. 4A, 5A, 6A and 7A are schematic side sectional views and FIGS. 4B, 5B, 6B and 7B are schematic top views.
That is, if a user inserts a disk 1, through an insertion hole 2a of an apparatus body 2, into a movable holder 3 provided in the inside of the apparatus body 2 (in a direction of an arrow X in FIG. 4), a motor not shown but provided in the inside of the apparatus body 2 is driven so that the disk 1 is led into the movable holder 3 automatically at a point of time when the disk 1 has been inserted to a certain position A (FIG. 5). At the same time, the movable holder 3 itself is loaded in the X direction to a reproducing position (position shown in FIG. 6) opposite to a photo pick-up 4 disposed in the inside of the apparatus body 2. That is, this is a state in which reproduction is enabled to be started. In this state, the photo pick-up 4 is located on a line L which is in a direction (disk scanning direction) Y perpendicular to the X direction (hereinafter also referred to as loading direction X) and which passes through a center point O of the disk 1.
When the disk 1 is rotated in this state and the photo pick-up 4 is moved in the disk scanning direction Y on the line L, an audio signal is reproduced from the disk 1.
On the other hand, in a recording mode, a magnetic head 5 is moved down to a recording position (see FIG. 7) so as to come into contact with the disk 1, so that the reproducing state shown in FIG. 6 is changed to a recording-enabled state. That is, this is a state in which recording is enabled to be started. In this state, the photo pick-up 4 and the magnetic head 5 vertically opposite to each other are located on the line L which is in the disk scanning direction Y and which passes through the center point O of the disk 1.
When the disk 1 is rotated in this state and the photo pick-up 4 and the magnetic head 5 are integrally moved in the disk scanning direction Y on the line L, an audio signal is recorded on the disk 1.
In order to control various operations such as leading of the disk 1 into the movable holder 3, loading of the movable holder 3, positioning of the disk 1 and the photo pick-up 4 by the loading in the reproducing position, descending of the magnetic head 5, positioning of the descended magnetic head 5 and the disk 1 in the recording position, and positioning of the disk 1 and the photo pick-up 4 in the reproducing position by ascending the magnetic head 5 which has been in the descended position, it is necessary to provide detecting switches for detecting the aforementioned positions and states in the apparatus body 2.
In this occasion, in order to detect the operations one by one accurately, it is ideal to provide an exclusive detecting switch for every operation. It is, however, difficult in terms of cost and practically impossible in terms of complication of an internal mechanism, a problem of arrangement space, etc. to provide a detecting switch for every operation. Therefore, a measure to allow all the operations to be controlled by the smallest number of detecting switches has been taken in the related photomagnetic recording/reproduction apparatus. Although there is a difference in accordance with the structure of the internal mechanism, all the operations can be generally controlled by three detecting switches.
That is, though not shown in FIGS. 4 to 7, there are provided an insertion position detecting switch SW1 for detecting the fact that the disk 1 has been inserted (that is, the disk 1 has been inserted to reach the position A shown in FIG. 5), a reproducing position detecting switch SW2 for detecting the fact that the movable holder 3 holding the disk 1 has reached the reproducing position (position shown in FIG. 6) of the disk 1, and a recording position detecting switch SW3 for detecting the fact that the magnetic head 5 has come into contact with the disk 1 in the reproducing position. Each of the detecting switches SW1 to SW3 is constituted by a limit switch.
The aforementioned various operations such as leading of the disk 1 into the movable holder 3, loading of the movable holder 3, positioning of the disk 1 and the photo pick-up 4 in the reproducing position by the loading, descending of the magnetic head 5, positioning of the descended magnetic head 5 and the disk 1 in the recording position, and positioning of the disk 1 and the photo pick-up 4 in the reproducing position by ascending the magnetic head which has been descended, are generally driven by one motor. Accordingly, configuration is made so that the series of operations interlock with one another mechanically. For this reason, the movable holder 3 holding the disk 1 moves delicately, for example, even in the case of a descending or ascending operation of the magnetic head 5.
As described above, each of the detecting switches SW1 to SW3 is constituted by a limit switch. The limit switch can perform accurate positional detection in one direction because the detection is made in a direction (open to close) in which a movable contact point comes into contact with a fixed contact point. There is, however, a problem that the limit switch can hardly perform accurate positional detection in the other direction because the detection is made in a direction (close to open) in which the movable contact point separates from the fixed contact point.
As described above, the reduction in number of detecting switches to the required smallest number, the mechanism configuration in various operations driven by one motor to interlock with one another, and the provision of the detecting switches each constituted by a limit switch make it possible difficult to perform positional detection accurately in one direction while make it difficult to perform positional detection accurately in the other direction. Hence, the following disadvantage occurs.
The disadvantage will be described below with reference to FIG. 8. FIG. 8 is a time chart showing the respective detecting switches SW1 to SW3 which are arranged rightward in a sequence of detection in the case where a disk I is loaded into the apparatus body 2. Each of the detecting switches SW1 to SW3 is arranged to make an operation of xe2x80x9copen to closexe2x80x9d when rightward force in FIG. 8 is applied to the switch. Further, the direction of rotation of the motor to move the disk 1 in a direction (rightward in FIG. 8) of insertion of the disk 1 into the apparatus body 2 is defined as a direction of reverse rotation (CCW) whereas the direction of rotation of the motor to move the disk 1 in a direction (leftward in FIG. 8) of ejection of the disk 1 from the apparatus body 2 is defined as a direction of forward rotation (CW).
That is, at the time of disk loading, the insertion position detecting switch SW1 changes from xe2x80x9cHxe2x80x9d to xe2x80x9cLxe2x80x9d when the disk 1 has reached the insertion position IN. The reproducing position detecting switch SW2 changes from xe2x80x9cHxe2x80x9d to xe2x80x9cLxe2x80x9d when the movable holder 3 holding the disk 1 has reached the reproducing position RP opposite to the photo pick-up 4. The recording position detecting switch SW3 changes from xe2x80x9cHxe2x80x9d to xe2x80x9cLxe2x80x9d when the magnetic head has been moved down to come into contact with the disk 1 in the reproducing position RP (that is, when the magnetic head 5 has reached the recording position RC). In this occasion, each of the detecting switches SW1 to SW3 makes a detecting operation of xe2x80x9copen to closexe2x80x9d as described above, so that accurate positional detection is performed.
That is, when the reproducing position detecting switch SW2 has detected the reproducing position RP the photo pick-up 4 is located accurately on the line L which passes through the center point O of the disk 1 as shown in FIG. 6. Similarly, when the recording position detecting switch SW3 has detected the recording position RC, the photo pick-up 4 and the magnetic head are also located accurately on the line L which passes through the center point O of the disk 1 as shown in FIG. 7.
On the other hand, when the disk 1 has been moved from the recording position RC to the reproducing position RP, that is, when the magnetic head 5 in contact with the disk 1 has ascended apart from the disk 1, the reproducing position detecting switch SW2 changes from xe2x80x9cLxe2x80x9d to xe2x80x9cHxe2x80x9d to detect the reproducing position RP. In this case, the reproducing position detecting switch SW2 makes a detecting operation of xe2x80x9cclose to openxe2x80x9d as described above, so that accurate positional detection cannot be performed. Specifically, detection of the reproducing position RP is delayed by a slight time (xcex94t) as shown in FIG. 8. This means that the position of the movable holder 3 relative to the photo pick-up 4 is shifted delicately in accordance with the delay xcex94t of detection of the reproducing position RP because the detecting operation of the reproducing position detecting switch SW2 interlocks with the operations of mechanism portions inclusive of the operation of the movable holder 3. That is, as shown in FIG. 9, the line L passing through the center point O of the disk 1 held in the movable holder 3 is shifted to the ejection side by xcex94P relative to the position of the photo pick-up 4.
For this reason, the chucking position of the disk 1 is displaced when a reproduction operation is started in this state. Hence, the disk 1 may be unable to rotate or the photo pick-up 4 may be unable to move in the scanning direction Y on the line L which passes through the center point O of the disk 1. Hence, there is a problem that clear reproduced sound cannot be obtained.
The present invention is achieved for solution of the aforementioned problem and an object thereof is to provide a photomagnetic recording/reproduction apparatus in which detection (especially, detection from a recording position RC to a reproducing position RP) of respective positions of a disk can be performed accurately without increase of the number of detecting switches and without complication of mechanism portions.
In order to achieve the above objects, according to the present invention, there is provided a photomagnetic recording/reproduction apparatus comprising:
a slot from which a photomagnetic disk is inserted in a first direction and ejected in a second direction;
a holder for accommodating the inserted photomagnetic disk therein;
a magnetic head for recording information onto the photomagnetic disk;
a optical pickup for reproducing information recorded in the photomagnetic disk;
a drive mechanism for moving the holder between an insertion position and a reproducing position and moving the magnetic head between an initial position thereof and a recording position, the insertion position at which the holder receives the inserted photomagnetic disk, the reproducing position at which the photomagnetic disk opposes to the optical pickup, and the recording position at which the magnetic head is brought into contact with the photomagnetic disk;
a first detector for detecting whether the photomagnetic disk is located at the reproducing position;
a second detector for detecting whether the magnetic head is located at the recording position; and
a mechanism controller for controlling the drive mechanism such that the holder first moves in the second direction toward a stop position where is apart from the reproducing position in a predetermined distance and then moves in the first direction toward the reproducing position in a case where the second detector detects that the magnetic head is apart from the recording position.
Preferably, the stop position is located between the insertion position and the reproduction position. Accordingly, the photomagnetic disk is prevented from unexpectedly running out from the slot.
Preferably, the first and second detectors include a limit switch respectively. Here, the limit switch is pressed in the first direction.
According to the above configuration, even in the case where each of detector is constituted by a switch such as a limit switch permitting accurate positional detection only in one direction (the first direction), positional detection in the other direction from the recording position to the reproducing position can be performed accurately without increase of the number of detector and without complication of mechanism operating portions. Namely, configuration is made so that detection in the other direction (the second direction) is the same operation as that in one direction to thereby solve the problem of detection error which occurs in detection in the other direction.